Nonefflorescing bar soap



Petenie'fi Mar. 3i, 1%

NONEFFLORESCING Baa soar Robert Franklin Heald, Nutley, N. 1., assignor to Colgate-Palmolive-PeetCompany, Jersey City, N. J., a corporation of Delaware No Drawing. Application June 20, 1939, Serial 13 Claims. (Cl. 252-109) This invention relates to an improved soap in bar form and more particularly to a soap bar containing alkaline soap builders, which bar of soap is substantially non-efilorescing. This application is a continuation-in-part of the Heald U. S. application Serial Number 69,527, filed March 18, 1936.

Household bar soaps usually. comprise fatty acid soaps and an alkaline soap builder such as sodium carbonate. Yellow laundry bar soaps also contain a ros'in soap which serves to reduce the cost, stabilize the soap and improve its efliciency for most purposes, To illustrate, a. general method of making yellow laundry bar soap is to prepare a soap base consisting of about ordinary soap produced from fats or oils such as tallow, and about ya rosin soap. Such soap' bases contain from 30 to 35% water. This soap base, in a relatively hot, liquid condition, is admixed in a crutcher with from 15m 25% of a concentrated solutipn of alkaline salts such as sodium silicate and sodium carbonate. The alkaline salts are added to improve the physical properties as well as the detergent properties of the soap. If sodium silicate alone is used as the' alkaline salt, the resulting bar may not be sufliciently hard for ordinary purposes. It has usually been necessary, therefore, to add sodium carbonate in relatively small proportions in addition to sodium silicate to increase the hardness of the soap. -While the addition of sodium carbonate imparts a desirable hardness to the soap bar, it also imparts to the bar a tendency to turn white or to bloom on the surface, due, it is believed, to the efilorescing of crystallized sodium carbonate. This efilorescence or bloom, which results in an objectionable appearance in the soap bar, apparently depends to a major extent upon the relative humidity of the surrounding atmosphere, usually developing very rapidly in cold dry weather, very often within 24 hours. It also occurs in warm weather, but somewhat more slowly because of the high humidity usually common to the summer months. This objectionable bloom or efflorescence occurs in bars both with white laundry soap and yellow laundrysoap, although it is more objectionable in bars of yellow laundry soap, as it is more apparent.

The present invention provides a soap in bar form suitable for laundry and other household purposes which contains alkaline soap builders, as well as possesses a desirable hardness, but which is substantially free from objectionable efliorescence or bloom on standing. The invention is applicable to both white laundry bar soap and yellow laundry bar soap, but inasmuch as the objection which it is designedto overcome is more apparent with yellow laundry soap than in bars of white soap, it is particularly advantageous for use in making bars of yellow laundry soap.

'In accordance with the present invention, improved bars of laundry soaps are produced by adding to the soap a solution of alkaline salts in a suitable manner. The solution of alkaline salts which is used contains, in addition to sodium carbonate, a proportion of sodium phosphate, preferably trisodium phosphate, and may contain sodium silicate. By the addition of sodium phosphate to the soap composition it is possible to produce a bar which has the desired degree of hardness and which doesnot form a bloom on the'surface caused by crystallization or eillorescence of sodium carbonate. The sodium phosphate, in addition to preventing the efllorescence or blooming, has a tendency to make the soap more translucent, tougher, more elastic, and less brittle.

Various sodium phosphates, such as trisodium phosphate, disodium phosphate, or sodium pyrophosphate, or mixtures of these, may be used, however, trisodium phosphate is somewhat more effective and is cheaper than the other sodium phosphates. The bars of the present invention are preferably prepared by producing a soap base and crutching into it a sodium silicate, soda ash, and trisodium phosphate, preferably as a mixed solution. This alkaline solution, for yellow soap, preferably contains from 2% to l /2% soda ash and 30 to10% hydrated trisodium phosphate, the balance being a sodium silicate solution containing about to solids. The proportions and amounts of the alkaline salts may be widely varied, however, as more or less sodium phosphate, and more or less sodium carbonate may be used, if desired. The sodium phosphate in the alkaline solution may be varied from about 35% to about 5%, and the sodium carbonate content may be as high as 10% or higher. In preparing filled, yellow soap in bars according to the present invention, it is preferred to use the solution in proportions rangingfrom between about 15% to about 25% of the final mixture. Instead of trisodium phosphate, other sodium phosphates may be used, or, a mixture of other sodium phoshates and caustic soda, such as a mixture of disodium phosphate and caustic soda, may be used. In efiect, using. a solution of disodium phosphate and caustic soda gives a solution of tion produced by dissolving trisorlium phosphate Example VII in water. Other alkali salts of these acids such i as those of potassium may be similarly employed. i i i percent The following examples are given for the pur m or tt8l 0lllpose of illustration and are not intended to be wmmsmon f lim1ting on the scope or the pres n inventlon- QOdmm pywphdsphm 12 5 2' o 'ater 25. 0 4. 0 Example I Sodium silicate solution (35 to 40% solidsl 62. 5 10.0 20 parts of an 8111180115 alkaline Solution Alkaline builder solution 100,0 10,0 .taining about It 2% of soda ash, hydrated l0 iy gg gg ggg n r) 4.0 trisodium phosphate, and 82 /2% of aqueous sodip "f F19 um silicatehaving a NazO/SiOz ratio of l/3.9 and mm a. solids content of about 38% is thoroughly admixed with 80 parts of a hot liquid soap base con- Example VIII taining about $4, ordinary fatty acid soap and /3 osin soap (dry basis) and containing 81 Disod um phosphatc. 5.5 L0 of water. The liquid soap mass containing the sgg u m silicate solution (as. to 40% solids)" 20.7 14.5 alkaline builder ispoured into forms and allowed f 7 to solidify by cooling. The resulting solidified i ggi ggiglgg somuon 2 soap is then converted into bars in the usual if fashion. The bar soap so produced is firm and 1 100.0 shows substantially no tendency to efiloresce or bloom. Example IX Example II or Soda ash 14,3 2 The procedure of Example I Is followefi but Hydrated trisodium 51.4 9.3 substituting for the aqueous alkaline solution 20 Water 34.3 6.0

0 1 parts of the following mixture. 2/ soda ash, Alkaline buildersolution 10M 17 5 hydrated trisodium phosphate, and 72 /2% Y ll w soap base 2.5 of the sodium silicate solution. 20 1 The following compositions represent other operative'combinations which may be produced as Example X indicated in Example I. In the Examples III. throu he s e yp y w soap b Hydmed "podium phosphate m0 L8 taming rosin soap is employed, Sodium silicate solution (35 to sclids) 90. 0 16. 3

I Alkaline builder solution 100. 0 1 1s. 1 Example III Yellow soap base 3L 9 Alkaline Percent 0 build e r totalcom- 40 Example XI Sodaash 7.5 .4 Hydrated trisodium phosphate 12. 4 '2. a drated tnsol mmp ospbate 35. 0 7. 8 Sodium silicate solution (35 to 40 solids). B0. 1 l4. 9 Sodium silicate solution (35 to 40% solids) 65. 0 l4. 5

Alkaline builder solution 100. 0 1s. 0' Alkaline builder solution 100. 0 22. a Yellow soap base s1. 4 i1 ell soap ase 77. 7

Example IV The following examples illustrate compositions r for the preparation of white soap in bars subsodush M 1,0 stantiallyv free from rosin soaps and containingyq ed trlsodlum phosphate 15.0 3.0 alkaline soap builders, which soap is substan- Sodium silicate solution (35 to 40% solids). 80 0 l6. 0 tiany free from a tendency to emoresceu Alkaline builder solution 100. 0 20. 0 Yellow soap base 80.0 Example XII Alkaline Percent builder total com- Ezcample V composition position 5 1 7 L5 BS 0.5 0.2 Hydrated trisodium phosphate"; 10.0 0 $3335 3]igaiz sol tgn f t t id Sodium silicate solution (85 to 40% solids) 82. 5 10. i caustics, d5 50] P 500 B o U: 2 6 Alkaline builder solution 100. 0 20.0 Soda 501mm" B 5 ""g i Alkaline builder solution m 42 0 White soap base 58:0 100.0

Example VI Example XIII Soda ash 7. 5 l. 5 Hydrated trisodium phosphate 4. 7 l. 8 Hydrated trisodium phosphate l5. 0 3. 0 Sodium silicate solution (35 to 40% solids) 91. 1 34. 6 Sodium silicate solution (35 to 40% solids). 77. 5 l5. 5 Caustic soda solution 40 B 4. 2 l. 6

Alkaline builder solution 100.0 20.0 Alkaline builder solution 100.0 38.0 Yellow soap base 80. 0 .White soap base 62. 0

It should be noted that these bar soap compositions on a dry basis comprise a major proportion of a soap base and a minor proportion of alkaline salts. On a wet basis the soap base preferably is at least 55% and the alkaline builder solution not more than 45% of the final composihydrated trisodium phosphate used should-preli-- erably not exceed about 9% of the finished soap. The alkaline salts preferably also include sodium carbonate in order to obtain an efficient soap at a lower cost bya saving on the quantity of sodium phosphate necessary to obtain the desired hardness. It is advantageous not to use more than about 2 /z% of sodium carbonate in the finished soap since it isdiflicult to control the efiiorescencc of soap containing a materially greater wrcentage of this salt and still obtain'a soap. of optimum hardness. Although sodium silicate is not essential, it. is preferred also-to include this material as part of the alkaline salts since this material economically improves the physical properties and washing characteristics of the'finished soaps.

Soap bars may be prepared by any of the common soap-making procedures from materials such as tallow, palm oil, coconut oil, olive oil, hydrogenated whale oil, hydrogenated fish oils, certain grades of cottonseedoil, garbage grease, oxidized mineral oils, tall oil, and wool fat, waxes, resins, the corresponding acids of said oils, fats, waxes and resins, or mixtures of any of the foregoing. One of the preferred methods for preparing soaps suitable for use in this invention from low-grade materials is that described in the U. S. Patent No. 1,918,603 to Martin Hill Ittner. It is possible when employing the process of this patent to incorporate the alkaline salts before, during, or immediately after the manufacture of the soap, thus avoiding the subsequent crutching step normally employed.

The new soap compositions may also contain any of the common auxiliary agents used in soap and detergent compositions. Suitable addition agents are other emulsifying agents including long-chain alcohol sulphate salts, monoglyceride monosulphate salts, salts of sulphonated mineral oil extracts, Turkey red oil, lecithin, ethanolamine soaps; other alkaline soap builders such as borax;

- ethylene, glycerine, ethyl alcohol, glycol, tetrahydrofurfuryl alcohol, phenol, cyclohexanol, water, Tetralin, Decalin, pine oil, mineral oil, mineral oil extracts, and naphtha; perfumes and deodorants; fats, oils, fatty acids, monoglycerides,

waxes, gums, glue and resins; germicides, such as phenol and organic or inorganic mercury compounds; any of the common water-soluble alkali metal or ammonium salts, and various'mixtures thereof. The type of addition agent to be used,

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will depend, of course, on the ultimate use of the new soap composition. The various ingredients may be mixed with the soap by any of the common methods suchas milling, stirring, kneading, crutching, fusing, and forming mixed solutions.

It will thus be seen that the present invention includes all common laundry soaps, both white and yellow, which include, in addition to the usual soap ingredients, alkaline salts for improving the bodiments thereof except as defined in the following claims.

I claim:

1. A non-efliorescing laundry bar soap containing from '75 to 85 parts of a soap base comprising about fatty acid soap and resin soap, dry basis, and "about 31% of water, and 25 to 15 parts of an aqueous alkaline solution containing up to 10% of sodium carbonate and 35 to 5% of hydratedtrisodium phosphate, the balance of said solution consisting of a sodium silicate containing from about 35 to about solids.

. 2. A non-eiiiorescing laundry bar soap containing from to parts of a soap base comprising about fatty acid soap and resin soap, dry basis, and about 31% of water, and 25 to 15 parts of an aqueous alkaline solution containing 2 to l of sodium carbonate and 30 to 10% of hydrated trisodium phosphate, the balance of said solution consisting of a sodium silicate containing from about 35% to about 40% solids.

3. A substantially non-efflorescing laundry bar soap containing from '75 to 85 parts of a soap base comprising about soap from fats and oils and resin soap, dry basis, and about 30 to 35% water, and 25 to 15 parts of an aqueous alkaline solution containing up to 10% of sodium carbonate and 35 to 5% of a sodium phosphate, the balance of said solution consisting of a sodium silicate containing from about 35 to about 40% solids.

4. A substantiallynon-efllorescing laundry bar soap comprised of '75 to 85 parts of a soap base containing about fatty acid soap and resin soap, dry basis, and with about 30-35%of water in said soap base, and 25 to 15 parts of an aqueous alkaline solutioncontaining 2 /z% to 7%% of sodium carbonate and 30 to 10% of hydrated trisodium phosphate, the balance of said solution consisting of a sodium silicate containing from about 35% to about 40% solids.

5. Bar soap comprising water, and, on a dry basis, a major proportion of a soap base and a minor proportion of sodium carbonate, sodium silicate and an alkaline sodium phosphate, the

amount of sodium carbonate being sufficient to cause objectionable efilorescence in the absence ofthesodium phosphate and the amount of sodium phosphate, ranging up to about 9% of the total composition, being suflicient to substantialdium phosphate, the amount of sodium carbonate ranging up to about 2/z% and being sufficient to cause objectionable efllorescence in the absence of the sodium phosphate and the amount of sodium phosphate being sufficient .to prevent substantially such efllorescence and ranging up to about 9% of the total composition to give desired hardness.

'7. Bar soap comprising at least about 55 parts v of a soap base and not more than about 45 parts of an aqueous alkaline solution containing sodium carbonate and sodium silicate together with a sodium phosphate, the amount of sodium carbonate being suiiicient to cause objectionable et- 1 to 12 and not more than 3 to 4, the amount of hydrated trisodium phosphate not exceeding 9% of the total bar, and the amount of sodium carbonate being. suflicient to cause blooming in the absence of the hydrated trisodium phosphate.

' 11'. The method of making bar soap which has substantially no tendency to eiiioresce which comprises gmixing sodium carbonateand trisodium phosphate with a water-soluble soap and forming the mixture intovbars, the amount of sodium carbonate being suflicient to cause objectionable efliorescence in the absence of the trisodium fiorescence in the absence oi the sodium phosphate and the amount of sodium phosphate, ranging up to about 9% oi the total composition to give desired hardness, being sumcie'nt to prevent substantially such efllorescence.

8. Bar soap comprising a major proportion of a soap base, sodium carbonate in amount ranging up to about 2/2% and sufflcient to cause objectionable eiilorescence in the absence of sodium I phosphate, and an alkaline sodium phosphate in amount ranging up to about 9% to give desired hardness and sufficient to prevent substantially such eiilorescence.

9. Bar soap comprising a major proportion of a soap base, sodium carbonate in amount sufficient to cause objectionable efilorescence in the absence of alkali phosphate, and a water-soluble alkali phosphate in amount ranging up to about 9% and suflicient to prevent substantially such efliorescence.

10. A substantially non -blooming laundry barsoap containing a major proportion of soap and a mixture of alkaline soap builders comprising sodium carbonate and hydrated trisodium phosphate, the proportion of sodium carbonate to hydrated trisodium phosphate being not less than phosphate and the amount of trisodium phosphate being suflicient to substantially prevent elflorescence' and not exceeding about 9% of the finished product.

12., The method of making bar soap which has substantially no tendency to, eflloresce which com- 1 prises mixing sodium carbonate and an alkalinecomprises mixing sodium carbonate and a water soluble alkali phosphate with a water-soluble soap and forming the mixture into bars,v the amount of sodium carbonate being suilicient to cause ob- J'ectionable eillorescence in the absence of the water-soluble alkali phosphate and the amount of the water-soluble alkali'phosphate being sumcient to substantially prevent'efliorescence and not exceeding about9% o! the finished product.

: ROBERT FRANKIIN HEALD. 

